1. Technical Field
This invention relates to a device for producing an aerosol from a gas and a liquid by atomizing the same within at least one nozzle located in a pressurized aerosol container and with a differential pressure sensor that determines the difference between the pressure in a gas infeed line and the pressure within the pressurized aerosol container.
2. Background Information
German Patent No. DE 101 39 950 A1 discloses a device for producing an aerosol from a gas and a liquid. The aerosol produced is available in a pressurized aerosol container at a given pressure above a liquid level, for example for lubricating and cooling cutting tools in lathes or milling machines. A differential pressure sensor serves to turn off an infeed of liquid (e.g., oil) and infeed of compressed gas (e.g., air) when a pressure differential is below a given minimum. However, this device is not able to smooth out variations in the compressed air supply, and lacks desired stability. Thus, it has been found that the internal pressure in the container can vary by about 1.5 bar when small volumes are withdrawn, so that it is between 2.5 bar and 4 bar. However, the amount of aerosol supplied to the user is then also subject to these variations. This is undesirable.
The optimal spraying action of an atomizer nozzle in which the aerosol is produced with minimal particle size depends on the design of the atomizer nozzle and is achieved at a given flow velocity of the atomizer air and a given throughput of air. In the aforementioned device, the atomizer nozzle works against the internal pressure of the pressurized aerosol container. Thus, the air throughput is determined by the pressure differential between the supplied compressed air and the internal pressure of the pressurized aerosol container, and thus changes with it. It has now been found that with the aforementioned device, particularly with severely varying withdrawal of aerosol, the atomizer nozzle very often does not operate in its optimal range, which is at a pressure differential of about 2 bar, for example. This then leads to the aerosol produced not having the desired minimal particle size. There is then the risk that the aerosol will partly separate out on the way to the point of use. This results in the liquid depositing within the nozzle, forming drops that block the flow of aerosol within the nozzle which aerosol is then not available at the point of use, or not in the required amount.